The 10 technologies that changed cars for the better during the 2000s.

PHOTOGRAPHY BY AARON KILEY, JORDAN BROWN, KEVIN WING, MORGAN SEGAL, AND THE MANUFACTURERS

December 2009

The past decade gave us steady increases in performance, fuel efficiency, and safety. Conventional wisdom says these attributes are at odds with one another—for example, safety can mean more size and weight, the enemies of performance and fuel economy, and the most-fuel-efficient car would be slow and small, the antithesis of safe or fast. But advances in technology have helped us get everything at once, whether it’s a formerly high-end feature that has trickled down to the masses or something brand-spanking new, and modern cars can satisfy the nanny-state bureaucrats and still raise our pulse when we put the gas pedal down.

Electronic Stability Control

Electric stability control (ESC, among other company-specific abbreviations) is a computer co-pilot that can keep your car on course if you unexpectedly lose grip. It began as a safety feature on the highest-end luxury cars, but the Aughties saw stability control move all the way down to entry-level vehicles. That's a good thing, because it's the first safety feature since the seatbelt that's been proven to save lives. At the same time, recent advanced systems actually improve lap times at the racetrack instead of hampering them and allow us F1-style technology like launch control on our daily drivers.

Gasoline-Electric Hybrid Drivetrains

They’re still less than five percent of the new-vehicle market, but hybrids are mass-media darlings. More important, the popularity of cars like the Toyota Prius has spurred advances in battery technology and motor efficiency that will help automakers to meet increasingly stringent fuel-economy and emissions standards.

Direct Fuel Injection

Squirting gas or diesel straight into the piston chamber instead of mixing it with air in the intake allows for higher compression and more precise fuel delivery, which increases efficiency and power. Once a gee-whiz feature of some luxury-car engines, direct injection is increasingly popular, even in four-cylinder economy cars, where the slightest gains can make a big difference.

Advanced/Variable/Compound Turbocharging

Variable-vane, twin-scroll, and sequential turbochargers are not new ideas. But advances in engine technology (such as direct injection), materials, and management have resulted in better turbocharged engines with less lag. Based on the current turbo offerings on the market, a future full of downsized engines—say, a turbo four where a V-6 might normally live—doesn’t look as bleak now as it did in 2000.

Dual-Clutch Transmissions

The dual-clutch transmission promised super-fast gearchanges and greater efficiency. But it started out as an expensive, clunky alternative to the automatic transmission when VW/Audi introduced it to the U.S. market mid-decade. A few years later, the dual-clutch transmission has come of age, and you can find one in everything from the Porsche 911 to the Ford Fiesta.

Torque-Vectoring Differentials

All-wheel drive in a performance car is a compromise: You get more accelerative grip, but you pay a penalty in weight. Torque vectoring doesn’t just move power between the front and rear axles. It can also dole out the horsepower from side to side. All of a sudden, what previously seemed impossible is easy, like driving an SUV on a racetrack (case in point, the BMW X6 M).

Lightweight Materials

If Ben Braddock (from The Graduate, youngsters) were graduating today, his dad’s friend would probably tell him, “One word: composites.” It’s not just plastics anymore, although that composite has found its way onto many an intake manifold. The past decade has seen improved methods in manufacturing aluminum, titanium, and magnesium, as well as mass production of carbon-fiber parts and even better use of high-strength steel. It all adds up to helping keep that evergreen promise to improve safety and efficiency without losing performance.

Satellite Radio and Multimedia Device Integration

The decade of the iPod has changed how we listen to music in cars. Where a simple auxiliary-in port was once rare, we’re now almost fully connected in the car. USB and Bluetooth connections integrate media players and phones directly into factory sound systems, and satellite radio has given us not just hundreds of stations of variety but also integrated data like traffic, weather, and gas-price information. Now our biggest problem seems to be putting down all the toys and remembering to drive.

Tire-Pressure Monitoring

As tires have developed over the years, flats have become far less common, which is generally good. And run-flat tires have improved and seen more widespread use. Both have turned us lazy at checking tire pressures for the rare times we do lose air. The result of the Ford Explorer/Firestone Tire fiasco—which could largely be blamed on improperly maintained air pressures, not faulty vehicles or tires—is government-mandated warning systems that help prevent flat-tire catastrophes for even the most maintenance-ignorant people.

High-Silica Rubber Compound for Tires

Of the many win-win developments in automotive technology from the 2000s, one of the best might seem like the least exciting. Bringing up tire compounds in a conversation will usually (at best) be met with blank stares. But the latest high-silica rubber tires give us better grip and better rolling resistance. If you think that’s boring, bear in mind that the 0.93-g skidpad performance of a Volkswagen GTI is due in large part to its modern tires.